This made me think twice about the Autotech pump.... ok it's by someone from APR but still an interesting read
Quote, originally posted by Keith@APR on VWVortex
As for cost, there are reasons. First of all, if we just wanted to release a handful of parts we could have done this last year. The design had already been tested for thousands of miles at that point and was proven. The issue with this product is ensuring that every single pump installed is 100% because a single bad part can spell disaster. QUALITY, QUALITY, QUALITY! Anyone here who is familiar with quality control especially when dealing with highly critical, incredibly precise parts understands this problem.
Let me briefly explain what will happen if a high pressure pump fails. These are not "scare tactics". This is an honest explanation of the damage that can occur if one of these pumps go bad! There are several scenarios and none are particularly pretty. In the best scenario, the fuel pump will simply seize on the down stroke. This will simply cause the engine to stall. The fuel pump can be removed and replaced. Another scenario would be the fuel pump seizing on the up stroke. This is a lot worse. This will cause a mechanical failure of the either the pump body, retaining bolts or it will break the intake camshaft in half (remember, the high pressure pump is directly driven off of the intake camshaft.) We have never tested this failure so I can't tell you which one will break first but in any case one of them will. Either of these scenarios can happen if the plunger to barrel clearance is not perfect or if there is some other geometric fault in the assembly. This is not something that can be verified by eye or by feel. We prevent these two situations by certifying ever single plunger/barrel assembly and by testing every single pump that leaves our facility. If there is a problem, we will catch it! Every single pump endures a testing cycle that includes being run at engine redline and full system pressure.
Another potential high pressure pump failure is leakage of fuel into the engine. This is a potentially catastrophic failure. Since the pump is cam driven, one side of the fuel pump has direct access to the engine's oiling system. If fuel leaks past the fuel pump into the engine, the fuel can dilute the engine oil. The driver may have no clue that this is occuring until it is too late. It does not take a tremendous amount of fuel to dilute the engine oil to the point that the oil loses its lubrication properties. When this occurs you can loses bearings, camshafts, lifters, turbochargers- basically time for a new engine. How can this occur? Very simply. A slight error during assembly and the seal is damaged. A faulty seal can also do this. Even just torquing the retaining nut to the wrong torque can distort the bore of the pump just enough to cause a failure. A tiny amount of extra clearance on the plunger/barrel and the seal won't be able to hold back the pressure (remember, one side of the piston can see up to almost 2000 psi.) There is only one way to verify that this won't happen. Test the pumps before they are put on cars!
It has been stated that the fuel pump parts are so easy to replace, so why not let the end user do it? Why don't hard drive manufacturers sell replacement platters for do it yourself installation? Heck, there is only like four screws holding a hard drive together? The answer is simple- it is way, way to easy to screw it up and the implications are potentially disastrous. And even if you didn't screw it up you don't know for absolute sure that the pump is good until you put it on the car and test it. We found this concept absolutely entirely unacceptable. Believe me, if we thought it was acceptable we would have done it- it would have eliminated a great deal of work in testing and certifying the pumps and we could definitely have sold the pumps for less (and probably many more of them)!
Our high pressure fuel pump tester takes care of the problem of verifying the pumps. This was a large engineering undertaking! I won't bore you with too many of the details (we will write an article on the tester soon) but all of the mechanicals and electronics are custom. It is an impressive machine. This was by far the most difficult portion of this project.
Anyways, every pump is tested and we have enacted numerous quality measures to ensure that we will have a 100% success rate with these pumps so that you guys won't have any problems. Every pump begins with a brand new OEM pump. This affects the cost of course. In the future we hope to have a rebuild program where people can send in their original pumps and we perform the modifications. This will help cost. We will also work to get the cost down in other areas as we ramp the production quantities up.
I hope I haven't scared anyone away from a high pressure pump upgrade. I am 100% confident in our product. It really is a great upgrade and it paves the way for many more exciting performance upgrades in the future!